What one can tolerate in a boss is individual. Someone I that once knew, who worked unbothered by her crazy boss in the entertainment industry, had survived a difficult childhood, living in her car until being helped by a concerned teacher who let her live with her until she graduated from college. Upon quitting her job the young woman was asked to train her replacement to tolerate the screaming boss. But when psychosomatic symptoms (as neck pain, etc.) begin it's time to leave. I've often said that I may not have been too smart about some of the jobs that I took but I always knew exactly when to leave, which is when they want you to stay. I've learned that a manager has a certain "shelf life," initially being viewed as the organization's savior but, after it functions well, as part of any lingering problem. Still, as my (now deceased) graduate school advisor said after receiving my tale of woe/complaining letter, "Think of the job as a chapter in your memoir." Sound advice from one that I still miss.